Esmaspäev 18. märts: The marsupial bulldog: omnivory, narrative & historical evidence
Thylacoleo carnifex was the size of a small lion: the largest marsupial predator to have ever lived. It existed during the Australian Pliocene and Pleistocene periods and, so it is argued, hunted large prey (sub-adult Diprodoton, rhinoceros-sized marsupial herbivores) by dispatching them with an extremely powerful bite. How do paleontologists get access to the ecological and behavioural features of critters long extinct? Historical scientists are in the business of reconstructing events in the deep past. Their evidence is often degraded, experiments are of limited value, and observations of contemporary systems sometimes provide little guide to past systems. And yet, historical scientists often provide rich, well-confirmed windows into the deep past. How do they do this? I argue that a sufficient explanation of scientific success in this arena must include at least two things. First, a recognition of the flexible, adaptive and opportunistic strategies historical scientist adopt: they are methodological omnivores. Second, understanding the evidential role that narrative plays in linking our picture of the past together. Via examining the science of T. carnifex, I’ll analyse these two notions and demonstrate their importance for successful historical science.

Teisipäev 19. märts: The unreasonable effectiveness of traces
Obdurodon tharalkooschild was an enormous platypus living in Australia around fifteen million years ago. The lineage’s existence only became known in the last decade, and only due to an entirely to a single molar tooth. Most philosophers and scientists, when reflecting on historical reconstruction, provide trace-centric accounts of how we access the past. In this paper I’ll present a problem for these accounts, before resolving and drawing lessons about how philosophers should think about evidence. Traces are the downstream remains of past events: fossils (of molars, for instance) and trackways in paleobiology, middens and ruins for archaeologists, background radiation for cosmologists, and so on. By tracing how such remains form, historical scientists infer from remains to the past. An account of methods in historical science is ‘trace-centric’ to the extent that it construes inferences from traces to the past as the main business of those methods.

In this paper, I’ll suggest that traces, as understood by trace-centric accounts, are unreasonably effective. A charge of ‘unreasonable effectiveness’, most common in mathematics, suggests that something works better than it ought to given our conception of it. The charge suggests some explanatory failure on the part of our understanding of that thing. In cases like O. tharalkooschild, highly stable, well-supported and rich reconstructions of the past are made on the basis of very small data-sets. On the face of it, if historical reconstruction is simply a matter of the relationship between traces and the past, these cases are problematic: surprising claims need a lot of evidence, and these claims apparently only require a few scrappy traces.
I’ll resolve this puzzle by emphasizing the role of middle-range theory, our knowledge of how traces form, which are required for taking traces as evidence in the first place. When we appeal to the fine-grained details of these—the amount of knowledge we have about how mammalian molars form, for instance—how so much can be done with so little is no longer puzzling. Traces are not unreasonably effective after all, but to understand them we need to attend to the local details. I’ll consider what upshots this has for abstract philosophical accounts of evidential reasoning, suggesting that their very abstractness obscures the local, explanatory detail.

Kolmapäev 20. märts: History is peculiar
The Cretaceous Terrestrial Revolution was a critical event shaping the modern world, seeing radiations in mammals, squamate lizards, snakes, birds and (maybe) dinosaurs, as well as the emergence of flowering plants (angiosperms) and their accompanying menagerie of pollinating insects. The revolution is at least in part thought to be related to the contemporaneous final breakup of Pangea into smaller continents, and the new angiosperm-insect alliance likely drove radiations in other lineages.

It is often thought that historical explanation is in some sense narrative explanation, or at least that history is particularly well-suited to narrative. Perhaps geographical changes from the relatively homogenous Pangea to the more heterogeneous modern continents led to a wider variety of habitats with more haphazardly distributed taxa, thus opening the door to diversification in the mid-Cretaceous. The earlier event (continental breakup) gains significance in terms of its downstream consequences, and a narrative explanation captures both link and significance. This connection between narrative and history has led some to ask whether there is some logic or essential property to narratives, others to draw links between the literary and the historical, and others to question whether narrative structures are discovered or constructed. I have a hunch about what makes narratives powerful answers to historical questions, which emerges from a hunch about why history matters for knowledge. History, I want to argue, matters when it generates ‘peculiarity’. Some target is peculiar to the extent that its modal profile is sensitive to the diversity-boosting or dampening features of the processes which produce or maintain it. Some processes are diversity-boosting rather than dampening, more likely to produce heterogeneous products than homogenous products. A single supercontinent is potentially diversity-dampening, as environments are homogenized and populations are less isolated: Pangea’s breakup then, could be diversity-boosting. The outcomes of these processes might themselves be robust or fragile, but what matters for peculiarity is that this robustness or fragility is explained as being the result of structures emerging from a diversity-boosting, or being maintained by a diversity-dampening, process. The insect-angiosperm alliance has proven remarkably stable and robust through the Cenozoic, yet is (perhaps) the result of a diversity-boosting process like the Cretaceous tectonic shifts. Because narratives are able to accommodate sequential changes over time, they are particularly well suited to capturing peculiarity. In addition to capturing narrative, this view accommodates a (relatively humble) realism about narratives: insofar as they describe peculiarity, historical narratives are discovered rather than invented. It also helps explain the localness of historical knowledge: history’s peculiarity often restricts regularities and patterns to within relatively narrow trajectories.

Teisipäev 21. märts: How to build a sea-urchin: simulations as smoking guns.
The echinoderms are an ancient lineage whose modern-day representatives include sand-dollars and sea-urchins. In the deep past, echinoderms were much more diverse. Prior to the end of the Paleozoic (around 250 million years ago), echinoderms boasted a wide variety of morphologies. What happened? In this paper, I’ll examine how the use of simulations and other models can help resolve questions about the deep past: that they can act as ‘smoking guns’. Carol Cleland’s notion of a ‘smoking gun’ refers specifically to new trace evidence which empirically discriminates between hypotheses about events in the deep past (the discovery of shocked quartz at the K-Pg boundary, for instance, favoured extra-terrestrial impact over mass volcanism occurring at the time). By developing simple geometric models of echinoderm development, paleontologists are able to examine under what conditions lead to various body-forms. I’ll argue that such results can provide genuine evidence which can distinguish between historical hypotheses: that is, that they are smoking guns. Simulations, then, can generate evidence about the past in a way analogous to (but not, I’ll argue, exactly the same as) observational evidence.